Steam reforming of hydrocarbons is commonly used for feedstock production for carbon-monoxide hydrogenation (Fischer-Tropsch synthesis), methanol synthesis and hydrogen production. Steam reforming is done commercially by flowing a mixture of steam and the hydrocarbon past a supported catalyst having an alumina support and a catalyst metal thereon, and reacting the mixture at a temperature from about 600° C. to about 1000° C., forming at least one product. Research has been done with the catalyst metal on many types of supports, including a spinel support. Residence times for conventional processes are typically on the order of seconds and steam to carbon ratio greater than about 2.5. For steam to carbon ratio less than 2.5, catalyst activity is generally degraded after hours to days due to coke formation and the supported catalyst must be refreshed or replaced.
The rate of supported catalyst activity degradation has been reduced in conventional processes by use of excess steam (steam to carbon ratio greater than 2.5). Excess steam, however, requires excess thermal energy and may result in a large system pressure drop. Using less steam results in faster degradation of catalyst activity because of coking from the hydrocarbon(s).
Hence, there is a need for a method of steam reforming of a hydrocarbon that provides greater product yield and permits using less steam and maintaining catalytic activity of the catalyst.